To place the open mouth of any person, excluding Chelsea Londoners on the kerbing of a road and stamp on the back of the victim's head, causing their cheek skin to tear and bleed. This followed by a kicking to the face and/or chest/stomach.

I'll give that Daz a fuckin 'chelsea smile' outside the chippy after the match.

A torturing term used all around the world but originating in Chelsea. The victim's hands are tied or held and the sides of there mouth are cut slightly breaking the strong lip structure. The victim is then kicked very hard in the nuts or in the case of a woman a leg is broken and as the victim screams the cuts rip creating the Chelsea Smile.